A cat told me that creating a mini-UE4 was not possible currently, at least not without a lot of know-how and people. If it is possible I would like to know how. If it is not possible I would like to submit this idea for some near future release. The idea would be to be able to remove modules and add them back in as desired, to remove unwanted complexity and reduce the size of the engine on the hard drive as desired and to improve performance by removing stuff as desired.
The editor currently has options that disables some plugins and features
Yeah I am aware of the ‘plugins’ box, but what about the other 1,000 modules( Unreal Engine API Reference | Unreal Engine Documentation ) Is there a way to selectively remove them and add them back in as wanted?
New systems are developed as plugins/modules easy to turn off. AI or Apex Destruction have been moved as separate module that you can disable.
You can disable VR stuff, online stuff. Lot of stuff 
I wouldn’t care that much about dozens of small modules like JSON parser.
It’s still just disabling compilation of some modules, or using it in runtime. Removing build products would just save few gigabytes…
Although I’d like to ask, why do you actually care? You need at least 256 GB SSD for game development + Windows, but it’s cheap nowadays. Actually 512 GB M.2 SSD is convenient and not that expensive.
About performance… it would mostly speed up rebuild of the entire engine. And that’s it. You still need tons of these small engine/editor modules.
You can disable plugins, but in an installed build, all modules are included and you can’t exclude them. But over the years I’m sure more things will move over to plugins so it should become increasingly modular.
it’s still important to save disc space, and too remove bloat wherever possible, but really it’s just about reducing complexity and then adding on as needed. I guess it will just have to be something for Epic people to consider developing in future release.
First, did you even check how much space a module occupies on disk before asking to be able to remove them to save disk space? This is a size map of my current 4.21 install:
The editor modules are in the Win64 folder, each one a DLL under 10MB each. So to save any meaningful space by removing modules, you’d need to remove hundreds of them, which would definitely cause breakage. You can save far more space by uninstalling support for platforms you’re not developing for (which is already possible), as you can see HTML5, Linux, Android and IOS files take significant space on the image above.
If you’re stuck with a small SSD, are using Windows 10 and really want to reduce UE4 disk space usage even more, open a command or powershell prompt in the UE4 installation dir and enter this command:
compact /C /S /EXE
This will apply the same real-time compression Windows 10 uses on its own executables to save space on small SSDs to the entire UE4 installation. This compression algorithm is optimized for executables, has negligible impact on loading times and will cut down the size by well over half. I recommend it if you have debug symbols installed: those .pdb and .o files take a lot of space and are easily compressed by over 4X.
This is my UE4.21 folder after compression. The “allocated” column shows the actual used disk space:
[QUOTE="Manoel.Neto;
compact /C /S /EXE
This will apply the same real-time compression Windows 10 uses on its own executables to save space on small SSDs to the entire UE4 installation. This compression algorithm is optimized for executables, has negligible impact on loading times and will cut down the size by well over half. I recommend it if you have debug symbols installed: those .pdb and .o files take a lot of space and are easily compressed by over 4X.
[/QUOTE]
Thanks that’s great information. But really it’s about complexity reduction, is there a way to pull out the vast libraries of stuff and add them back in as desired? So the lists are smaller.